JPH0624539A - Sensor input circuit for label exfoliating machine - Google Patents

Abstract

PURPOSE:To form a confirmation loop for a label exfoliating machine to start stable label feeding. CONSTITUTION:The detection output of a phototransistor 1 is output after a comparator 2 compares it and a single shot FF3 delays the input from the comparator 2 by time constant (t) of C1, R1. This output and the output of the comparator are input to an AND circuit 4, the output of this circuit 4 is inverted by an inverter 5 and then passes filters R2, C2, and the resulting data is inverted by an inverter 6 to be a motor control signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control of a drive motor of a label peeling machine which conveys a label on a conveyor.

[0002]

2. Description of the Related Art Conventionally, a sensor detects a position of a work (component on the conveyor) sent on a conveyor, and a motor driving the conveyor is turned on / off by opening / closing a relay by the detection signal. There is a transfer technique for adjusting the feed speed of the conveyor according to the work process.

[0003]

However, in the prior art, when a small work such as a label is fed onto the conveyor and the feeding speed of the conveyor is changed in a relatively short time, that is, the motor is turned ON / OFF relatively. When it is necessary to repeat the operation at short time intervals, there is a problem that chattering of the motor or external light picked up by an optical sensor for detecting a work causes a malfunction.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a sensor input circuit of a label peeling machine capable of preventing a motor chattering and a malfunction due to external light.

[0005]

To achieve the above object, a comparator for comparing and outputting an input from an optical sensor for detecting the presence or absence of a label, and a delay for a time determined by a CR time constant by inputting the output of the comparator. A single shot FF for outputting, an AND circuit for inputting the H output of the single shot FF and the comparator for L output, a first inverter for inputting the L output of the AND circuit for inverting output, and the first inverter And a second inverter which inputs the output of the filter circuit and outputs the inverted output.

[0006]

With the above structure, the presence or absence of the label conveyed on the conveyor is detected by the optical sensor, and the detection output is compared and output by the comparator. The single shot FF, to which the output of the comparator is input and the delay time determined by the CR time constant is set, starts with a delay of the determined time. The AND circuit is the comparator H
The output and the delayed H output are input and L output is performed. AN
The L output of the D circuit is inverted by the first inverter,
L inverted by the second inverter through the filter
Since it is output to the motor circuit as an output, the motor control signal is delayed and output with respect to the detection signal of the optical sensor, and it is possible to prevent malfunction due to chattering or external light picked up by the optical sensor.

[0007]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit diagram of a sensor input circuit according to an embodiment of the present invention. In FIG. 1, 1 is a phototransistor that receives light from the infrared light emitting diode 7 when the label 8 is not present, and 2 is an inversion that compares the detection output of the phototransistor 1 with a threshold value (threshold level) Type comparator. The photosensor may be an emitter load type instead of an open collector and the comparator may be a non-inverting type. Vs is a comparator reference voltage.

3 receives the output of the comparator 2 and inputs C
1 is a single shot FF (flip-flop) IC that outputs an output delayed by a time t determined by R1 from Q / (inversion terminal of Q). 4 receives the H output of the comparator 2 and the Q output H of the single shot FF3,
A NAND circuit for output, 5 is an inverter that inverts the output of NAND 4 and outputs H, R2 and C2 are low-pass filters, and 6 is an inverter that further inverts and outputs L output to the motor circuit.

FIG. 2 is a flow chart of the processing of the embodiment shown in FIG. FIG. 3 is a timing chart of signals in the embodiment shown in FIG. In FIG. 3, a, b, c, d,
e represents a signal waveform at points a, b, c, d, and e in FIG. FIG. 4 is an explanatory diagram of a label feeding state.

Next, the operation will be described with reference to the drawings. First, as shown in FIG. 4, the label 8 on the conveyor driven by the motor is attached to the light emitting diode 7 and the phototransistor 1.
Detected by the optical sensor of.

As shown in FIG. 3A, the potential at the point a becomes High level because the phototransistor 1 is OFF when the label 8 is present, and the phototransistor 1 receives the light when the label passes. Turns on and point a is L
ow level. The comparator 2 compares this detection output with the reference voltage Vs and inverts the output as shown by b. By setting the reference voltage value in this case, noise due to external light is suppressed and reduced.

Next, the inverted output of the comparator 2 is input to the B terminal of the single shot FF3. Cext,
C1 and R1 (variable) connected to the Rext / Cext terminals
The output delay time t of the single-shot FF3 is freely set by the time constant of, but in this case, about t = C1
R1 is adjusted and set to × R1 = 0.45S.

Thus, t = 0.45S for the input
Delayed start Q terminal output shown at c and B terminal b
The signal of is input to the NAND 4 to obtain an L output as a signal delayed by t = 0.45S from the detection timing of the phototransistor 1 of b, and inverted by the inverter 5 to be an H output like d. , R2, C2 low pass filters are used to remove unnecessary pulses, and the motor 6 is inverted by the inverter 6 for motor control and output as a motor start signal with an L output such as e.

With this processing, it is possible to absorb the influence of chattering of the motor immediately after switching and external light noise within the delay time t.

Therefore, this will be explained as a processing operation of the entire label peeling machine with reference to the flow chart of FIG. 2. Whether or not there is an input from the phototransistor 1 is discriminated by the comparator 2 (step S10). If it is passing the label, return to the original. If there is an input, since the label has already passed, it is necessary to instruct the motor start and send the label, so the timer is started (step S11). This processing is to invert the single shot FF3 by the output of the comparator 2 and send out the Q output delayed by the timer time t.

Next, the presence / absence of an input is determined (step S12), which is a process of inputting the output of the comparator 2 and the Q output of the single-shot FF3 by the NAND 4 and outputting L. If there is no input and there is no output from NAND4, it returns to the original state, and if there is output, the output is inverted by inverters 5 and 6 and sent as a motor start signal to the motor circuit as a start signal after t time, and label feeding. Is performed (step S13).

In this embodiment, after the phototransistor of the optical sensor detects the presence or absence of the label,
By performing the delay timer control for t time, the confirmation loop is configured, and it is possible to suppress the malfunction due to chattering or external light. The L level and the H level in the above example may be set so as to be unified and opposite.
In that case, each logic circuit and logic gate are correspondingly changed.

[0018]

As described above, according to the present invention, a comparator for comparing and outputting an input from an optical sensor for detecting the presence or absence of a label and an input from the comparator are output with a time delay determined by a CR time constant. Single-shot FF and AND that inputs both H outputs and outputs L
The L output of the circuit and the AND circuit is inverted by an inverter, passed through a low-pass filter, and further inverted by the inverter to form a control loop for the motor control output, which has the effect of preventing motor chattering and malfunction due to external light. is there.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a sensor input circuit of a label peeling machine according to an embodiment of the present invention.

FIG. 2 is a flowchart of processing of the embodiment shown in FIG.

FIG. 3 is a timing chart of signals in the embodiment shown in FIG.

FIG. 4 is an explanatory diagram of a label feeding state.

[Explanation of symbols]

 1 Phototransistor 2 Comparator 3 Single Shot FF 4 AND Circuit 5, 6 Inverter 7 Light Emitting Diode 8 Label

Claims (1)

[Claims] 1. A comparator for comparing and outputting an input from an optical sensor for detecting the presence or absence of a label, a single shot FF for inputting the output of the comparator and delaying the output for a time determined by a CR time constant, and the single shot FF. An AND circuit that inputs the H output of the comparator and outputs the L output, a first inverter that inputs the L output of the AND circuit and outputs the inverted output, a filter circuit connected to the first inverter, and the filter A sensor input circuit for a label peeling machine, comprising a second inverter for inputting an output of the circuit to make an inverted output.